Numerical Modeling of Laser-Driven Plasma Experiments Aiming to Study Turbulent Dynamo and Thermal Conduction at the National Ignition Facility*

Dynamo in astrophysical turbulence is a key process for the amplification of magnetic fields in the early universe. The advent of high-power laser systems, along with the scaling of magnetohydrodynamics (MHD), has made it possible to recreate astrophysical conditions and processes in terrestrial laboratories. We present 3-D radiation-MHD FLASH simulations used to design and interpret laser-driven plasma experiments of fluctuation dynamo at Lawrence Livermore National Laboratory’s National Ignition Facility. The experiments aim to demonstrate dynamo amplification in the large magnetic Prandtl number regime, which is relevant for magnetic-field amplification in galaxies and galaxy clusters. The simulations show that the experiments can achieve a turbulent plasma state with magnetic Reynolds numbers in excess of 10^4 and magnetic Prandtl numbers above unity. The dynamo-amplified magnetic fields in the simulations are strong enough that the electron Larmor radius is smaller than the mean free path in the turbulent plasma. The suppression of electron heat transport under such conditions is incorporated in the simulations by switching off the electron conductivity to assess its effects on the plasma properties.